1. Field of the Invention
The present invention is directed to the field of surface cleaning and etching of silicon substrates and more specifically to an improved apparatus for enhancing those processes.
2. Description of the Prior Art
The use of ultrasonic energy to generate cavitation in cleaning solutions and thereby enhance cleaning action is a common, well established practice and is described in U.S. Pat. Nos. 3,198,489; 3,240,963; and 4,401,131.
A more recent innovation in this area is my earlier invention described in U.S. Pat. No. 4,602,184, which is incorporated herein by reference.